When designing a charge pump as a design engineer, the following factors must be considered:

· High conversion efficiency · No adjustment of capacitive charge pump 90%

·Adjustable capacitive charge pump 85%

· Switching regulator 83%

· The quiescent current should be small, which can save more power;

· The input voltage should be low to make full use of the potential of the battery;

· The noise should be small, without interference to the overall circuit of the mobile phone;

· High degree of functional integration, improving the efficiency of use per unit area, making the design of mobile phones more compact;

Adequate output adjustment capability, charge pump will not be hot due to work at full load;

Small package size is a common requirement for handheld products;

Low installation cost, including the peripheral circuit occupying a small area of ​​the PCB board, and the traces are small and simple;

· With a closed control terminal, the charge pump can be switched off during long standby periods, so that the supply current consumption is almost zero.